Firmware update script py3 conversion

[JanezCim]

Trying to solve #149

I added .encode() because i was experiencing:

raise TypeError('unicode strings are not supported, please encode to bytes: {!r}'.format(seq))
TypeError: unicode strings are not supported, please encode to bytes: "b'

But then I added Int() because:

  File "/home/ubuntu/catkin_ws/src/ubiquity_motor/scripts/upgrade_firmware.py", line 233, in send
    chr((len(self.out) / 1) % 256),
TypeError: integer argument expected, got float

And now im getting:

  File "/home/ubuntu/catkin_ws/src/ubiquity_motor/scripts/upgrade_firmware.py", line 261, in send
    raise Exception("Packet did not start with valid start byte, instead: " + cstr(start_byte) + " -- header: " + cstr(header))
Exception: Packet did not start with valid start byte, instead: <class 'bytes'> -> b'~' -- header: <class 'bytes'> -> b'~<0\x00'
 

and I cant solve it. Do you have any ideas how to go around this @rohbotics? I maybe going at it from a totally wrong angle?

[mjstn]

Rohan has been converting the firmware upgrade script for a few weeks now. This is a duplicate issue of some other issue.

[JanezCim]

yes you mean #149 , but this is a draft PR, not an issue, here im trying to colaborate with rohan to actually solve it. And as far as I could see there was no branch to this goal. I got myself into this because im working on OTA update for Noetic and this script first needs to work in order for that to work.

[JanezCim]

just FYI on ota_update this has been kindof patched here https://github.com/UbiquityRobotics/ota_update/pull/13 by simply installing python2 onto the same system. This is a very bad solution long term, but for now it works. When Firmware update script gets updated to py3, this should immediately be fixed also on ota_update repo

[JanezCim]

This py2 hack is now also planned on being used in firmware images in https://github.com/UbiquityRobotics/pi_image2 so when py3 conversion is done, someone should also check to update the commands there